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包装与食品机械 1986年第3期 64-67页

作者： marvin m fein 严明

一种新型的芳香族聚合物、商业名称为Xydar的热塑性树脂,现在已出现在包装领域。这种树脂在熔融状态下分子是取向的,所以又称之为液晶聚合物。由于分子的取向性,该树脂的各项特性指标都达

关键词：热塑性树脂热稳定性 TGA 热力学性质注射模塑变形温度宇宙空间环境燃烧性能阻燃性挠曲特性 SRT 平方英寸破断韧性力学强度断裂韧性结晶点

Boron-containing compounds as labels,drugs,and theranostic agents for diabetes and its complications

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World Journal of Diabetes 2024年第6期15卷 1060-1069页

作者： marvin A Soriano-Ursúa R Ivan Cordova-Chávez Eunice D Farfan-García George Kabalka Department of Physiology Escuela Superior de MedicinaInstituto Politécnico NacionalCiudad de México 11340Mexico Department of Physiology Instituto Politécnico NacionalMexico City 11340Mexico Department of Biochemistry Instituto Politécnico NacionalMexico City 11340Mexico Department of Chemistry The University of TennesseeKnoxvilleTN 37996United States

Diabetes is a disease with a high global *** strategies have failed to limit the advancement and impact of the *** early diagnosis and treatment will require the development of new *** this sense,boroncontaining compounds have been reported as agents with the ability to reduce glycemia and *** have also been used for labeling and measuring carbohydrates and other molecules linked to the initial stages of diabetes and its *** addition,certain boron compounds bind to molecules related to diabetes development and their biological activity in the regulation of elevated ***,it should be noted that some boron compounds appear to exert beneficial effects on diabetes complications such as accelerating wound healing while ameliorating pain in diabetic patients.

关键词： Boron Carbohydrates metabolism Diabetes Boronodipyrromethene

Temporal allocation of metabolic tolerance in the body of beet armyworm in response to three gossypol-cotton cultivars

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Science China(Life Sciences) 2009年第12期52卷 1140-1147页

作者： marvin K HARRIS Department of Entomology Texas A&M University of USA

The nutrient composition and enzyme activities in larvae of the beet armyworm, Spodoptera exigua (Hbner), fed on high, medium or low gossypol cotton cultivars were examined at different time intervals. Significantly lower free fatty acid was observed in larvae fed for 6 h on high gossypol 'm9101' compared to larvae fed on the low (ZmS13) and intermediate (HZ401) gossypol cultivars. Significantly higher trypsin activity was observed in larvae fed on high gossypol 'm9101' for 24 h compared to those fed for 1, 4 and 6 h. Significantly higher catalase and total superoxide dismutase enzyme activities were observed in larvae of S. exigua fed on high gossypol 'm9101' compared with low gossypol cultivars 'ZmS13' and 'HZ401' for 1, 4, 6 and 24 h. However, significantly lower carboxylesterase and acetylcholinesterase enzyme activities were found in larvae fed on high gossypol 'm9101' compared with the other cultivars for 1, 4, 6 and 24 h. The interaction between cotton variety and beet armyworm infestation time significantly affected the carboxylesterase enzyme activity in S. exigua. The characterization of the effects of plant allelochemicals on herbivorous larvae is important for aiding understanding of plant-insect interaction as well as in devising solutions to pest problems by breeding plant resistance, identifying metabolic targets for insecticide development, etc.

关键词： Spodoptera exigua gossypol free fatty acid detoxification enzyme acetylcholinesterase total superoxide dismutase

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GC/mS: A Practical User's Guide, Second Edition 2nd ed.

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Effect of tibolone pretreatment on kinases and phosphatases that regulate the expression and phosphorylation of Tau in the hippocampus of rats exposed to ozone

2008年

作者： marvin C. mcmaster(auth.)

来源：畅想之星图书光盘版（南... 评论

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Neural Regeneration Research 2018年第3期13卷 440-448页

作者： Rodolfo Pinto-Almazán Julia J. Segura-Uribe marvin A. Soriano-Ursúa Eunice D. Farfán-García Juan m. Gallardo Christian Guerra-Araiza Unidad de Investigación Hospital Regional de Alta Especialidad Ixtapaluca Carretera Federal México-Puebla km 34.5 C.P. 56530. Ixtapaluca State of Mexico Mexico Institute for the Developing mind Children's Hospital Los Angeles Los Angeles CA USA Department of Pediatrics Keck School of Medicine University of Southern California Los Angeles CA USA Unidad de Investigación médica en Enfermedades Neurológicas Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico Escuela Superior de medicina Instituto Politécnico Nacional Plan de San Luis y Diaz Mirón Col. Casco de Santo Tomis. C. P. 11340. Mexico City Mexico Unidad de Investigación médica en Enfermedades Nefrológicas Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico Unidad de Investigación médica en Farmacologia Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico

Oxidative stress （OS） is a key process in the development of many neurodegenerative diseases, memory disorders, and other pathological processes related to aging. Tibolone （TIB）, a synthetic hormone used as a treatment for menopausal ymptoms, decreases lipoperoxidation levels, prevents memory impairment and learning disability caused by ozone （O3） exposure. However, it is not clear if TIB could prevent the increase in phosphorylation induced by oxidative stress of the microtubule-associated protein Tau. In this study, the effects of TIB at different times of administration on the phosphorylation of Tau, the activation of glycogen synthase kinase-3β （GSK3β）, and the inactivation of Akt and phosphatases PP2A and PTEN induced by O3 exposure were assessed in adult male Wistar rats. Rats were divided into 10 groups： control group （ozone-free air plus vehicle [C]）, control ＋ TIB group （ozone-free air plus TIB 1 mg/kg [C ＋ TIB]）; 7,15, 30, and 60 days of ozone exposure groups [O3] and 7, 15, 30, and 60 days of TIB 1 mg/kg before ozone exposure groups [O3 ＋ TIB]. The effects of O3 exposure and TIB administration were assessed by western blot analysis of total and phosphorylated Tau, GSK3β, Akt, PP2A, and PTEN proteins and oxidative stress marker nitrotyrosine, and superoxide dismutase activity and lipid peroxidation of malondialdehyde by two different spectrophotometric methods （marklund and TBARS, respectively）. We observed that O3 exposure increases Tau phosphorylation, which is correlated with decreased PP2A and PTEN protein levels, diminished Akt protein levels, and increased GSK3β protein levels in the hippocampus of adult male rats. The effects of O3 exposure were prevented by the long-term treatment （over 15 days） with TIB. malondialdehyde and nitrotyrosine levels increased from 15 to 60 days of exposure to O3 in comparison to C group, and superoxide dismutase activity decreased. Furthermore, TIB administration limited the changes induced by O3 exposure. Our results

关键词： tibolone oxidative stress ozone exposure Tau GSK3 hippocampus neuroprotection

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Altered Oncogene Activity Contributes to Compensation for Antisense Suppression of Bcl-2 and Tumor Resistance

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Open Journal of Apoptosis 2015年第3期4卷 62-70页

作者： marvin Rubenstein Courtney m. P. Hollowell Patrick Guinan Division of Cellular Biology Hektoen Institute for Medical Research Chicago IL USA Division of Urology Stroger Hospital of Cook County Chicago IL USA Department of Biochemistry Rush University Medical Center Chicago IL USA Department of Urology Rush University Medical Center Chicago IL USA Department of Urology University of Illinois at Chicago Chicago IL IL USA

Antisense oligonucleotides (oligos) have targeted growth regulatory proteins in prostate cancer models. To identify compensatory alterations in the expression of non-targeted genes we evaluate mono- and bispecific oligos targeting and equally suppressing the expression of the apoptosis inhibitory protein bcl-2. Bcl-2 is chosen because oligos directed towards it have entered clinical trials to restore apoptosis in cancer patients. Treated LNCaP cells compensate for the diminished bcl-2 by suppressing caspase-3 (an apoptosis promoter) while enhancing expression of AKT-1 (another apoptosis inhibitor), androgen receptor (AR) and its (p300 and IL-6) coactivators. Additional proteins are enhanced including PD-1, its ligand PD-L1 (immune checkpoint blockade markers) and fas-ligand, which activate apoptosis through the signal transduction, along with suppressor protein p53, polymerase transcription mediator mED-12 and signal transducer STAT-3. These alterations in expression may contribute to a greatly enhanced expression of the proliferation marker KI-67. This suggests that therapeutic approaches to restore apoptosis through suppression of bcl-2 lead to an altered expression in non-targeted genes involving apoptosis, androgen sensitivity, transcriptional activity and immune responsiveness, leads to an increase in proliferation (and a more androgen driven aggressive phenotype). In this study we evaluate the expression of two oncogenes (v-myc and K-ras) and find a large and significant enhancement of v-myc activity, which is produced by oligos targeting bcl-2 at the 5’ position. For K-ras, although significant suppression is produced by the bispecific targeting bcl-2 at the 3’ position, the percent change is relatively small compared with other compensatory alterations we have measured, and much less than in v-myc. Therefore, for the two oncogenes being evaluated, only increased v-myc activity is probably large enough to contribute to increased tumor aggressiveness in compen

关键词： Antisense Oligonucleotides Prostate Cancer Bcl-2 Gene Compensation Therapy

Following Inhibition of BCL-2 by Antisense Oligonucleotides Compensatory Suppression of Apoptosis Involves the Direct Signal Transduction Pathway of LNCaP Cells

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Open Journal of Apoptosis 2015年第1期4卷 1-10页

作者： marvin Rubenstein Courtney m. P. Hollowell Patrick Guinan Division of Cellular Biology Hektoen Institute for Medical Research Chicago IL USA Department of Biochemistry Rush University Medical Center Chicago IL USA Department of Urology Rush University Medical Center Chicago IL USA Division of Urology Stroger Hospital of Cook County Chicago IL USA Department of Urology University of Illinois at Chicago Chicago IL USA

Previously we have shown that when LNCaP cells are treated with antisense oligonucleotides (oligos) directed against BCL-2, compensatory changes in non-targeted genes take place in attempts to restore apoptosis and promote tumor aggressiveness. In addition to the inhibition of BCL-2, we find that the apoptosis promoter caspase-3 activity is suppressed, the transcription activity of STAT-3 is enhanced, while other regulators (bax, clusterin, AKT-1) associated with mitochondrial regulated apoptosis and caspase cascade are either unchanged or undetectable. We now evaluate proteins associated with the second pathway of apoptosis activation mediated by direct signal transduction involving fas, fas-ligand (a tumor necrosis factor-like cell surface receptor aka CD95), as well as the similar programmed death cell surface receptor (PD-1) and its respective ligand (PD-1L). This study evaluates the growth inhibition of in vitro propagating LNCaP cells employing mono- and bispecific oligos directed against BCL-2 [the second binding site was directed against the epidermal growth factor receptor (EGFR)];and employing RT-PCR. The expression of these four proteins was evaluated. Expression of fas-ligand, PD-1 and PD-L1 were all significantly enhanced, whereas fas itself was undetectable. This suggests that in addition to pathways associated with the mitochondrial pathway of apoptosis, compensatory changes occur in the direct signal transduction pathway of this process. In addition to alterations in androgen sensitivity, growth factor expression and oncogene expression, these data suggest that suppressive BCL-2 therapy involves multiple pathways, including those involved with immune targeting and cytotoxicity and must be taken into account to make gene therapy more efficacious.

关键词： Antisense Oligonucleotides Prostate Cancer Fas Fas-Ligand PD-1 PD-1 Ligand Caspase-3 BCL-2 Bax Therapy

Influence of “mild” Sonication Conditions on the Characteristics of <i>Streptococcus thermophilus</i>ST-m5

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Advances in microbiology 2012年第1期2卷 8-16页

作者： marvin moncada Kayanush J. Aryana School of Animal Sciences Louisiana State University Agricultural Center Baton Rouge USA

mild sonication intensity is an acoustic energy which involves the conversion of electrical signal into a physical vibration modifying the permeability of the cell plasma membrane. The objective of this study was to determine the effect of mild sonication intensities at different temperatures on growth, bile tolerance and protease activity of Streptococcus thermophilus. The treatments were four mild sonication intensities (8.07, 14.68, 19.83 and 23.55 W/cm2) randomized at three different temperatures (4°C, 22°C and 40°C). The energy input (1500 J) was kept constant in all treatments. Control samples did not receive any sonication treatment. Growth and bile tolerance were determined every two hours for 12 h of incubation. Protease activity was determined at 0, 12 and 24 h. mild sonication conditions included a) mild sonication intensities, b) temperatures and c) times, all three of which played a role in influencing the desirable attributes of Streptococcus salivarius ssp. thermophilus ST-m5. Of all the mild sonication intensities studied, 14.68 W/cm2 had the best overall influence at certain time points for improving bile tolerance and growth at 4°C, growth at 22°C and bile tolerance and growth at 40°C of Streptococcus salivarius ssp. thermophilus ST-m5. mild sonication intensity of 23.55 W/cm2 had the overall best influence at certain time points for protease activity of Streptococcus salivarius ssp. thermophilus ST-m5 at 40°C. Streptococcus thermophilus ST-m5 pretreatment with some mild sonication conditions can be recommended for improvement of some of its characteristics.

关键词： Sonication Starter Culture Streptococcus thermophilus

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静、动荷载作用下索支管结构的性能评估

天津大学学报（自然科学与工程技术版） 2019年第A02期52卷 83-89页

作者： marvin Paul Agwoko 陈志华史文浩卢杰天津大学建筑工程学院天津300072 天津大学水利工程仿真与安全国家重点实验室天津300072 天津大学沿海民用建筑安全教育部重点实验室天津300072

索支管结构(CISS)是一种新型的索桁架空间结构,在应用于高架管道时具有一定的经济性.桁架构件的数量、结构跨中高度和宽度决定了结构的静力和动力性能.因此基于桁架构件数量和跨中高度设计了2套方案,对64.8 m跨度的索支管结构进行了几... 详细信息

索支管结构(CISS)是一种新型的索桁架空间结构,在应用于高架管道时具有一定的经济性.桁架构件的数量、结构跨中高度和宽度决定了结构的静力和动力性能.因此基于桁架构件数量和跨中高度设计了2套方案,对64.8 m跨度的索支管结构进行了几何参数化分析.结果表明,与桁架构件数量较少的方案2相比,桁架构件数量较多的方案1具有较大的整体刚度.在竖向荷载作用下,跨中高度对具有较高承载力的S1/1和S2/4模型的影响较大,但动力响应较差.由分析数据可知,与模型S1/2和S2/5相比,模型S1/1、S1/3、S2/4和S2/6有较大的侧向位移,导致动力响应较差.研究表明,CISS结构的静力和动力响应不仅与拉索预拉力有关,还与几何参数,特别是跨中高度密切相关.

关键词：索支管结构桁架数量跨中参数刚度动力响应

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Improving photosynthetic efficiency toward food security:Strategies,advances,and perspectives

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molecular Plant 2023年第10期16卷 1547-1563页

作者： Edward N.Smith marvin van Aalst Tiina Tosens Ülo Niinemets Benjamin Stich Tomas morosinotto Alessandro Alboresi Tobias J.Erb Paul AGómez-Coronado Dimitri Tolleter Giovanni Finazzi Gilles Curien matthias Heinemann Oliver Ebenhöh Julian m.Hibberd Urte Schlüter Tianshu Sun Andreas P.m.Weber Faculty of Science and Engineering Molecular Systems Biology–Groningen Biomolecular Sciences and BiotechnologyNijenborgh 49747 AG Groningenthe Netherlands Institute of Quantitative and Theoretical Biology Cluster of Excellence on Plant Science(CEPLAS)Heinrich Heine UniversityUniversitätsstrasse 140225 DüsseldorfGermany Institute of Agricultural and Environmental Sciences Estonian University of Life Sciences51006 TartuEstonia Institute of Quantitative Genetics and Genomics of Plants Cluster of Excellence on Plant Science(CEPLAS)Heinrich Heine UniversityUniversitätsstrasse 140225 DüsseldorfGermany Department of Biology University of Padova35131 PadovaItaly max Planck Institute for Terrestrial microbiology Department of Biochemistry&Synthetic Metabolism35043 MarburgGermany Interdisciplinary Research Institute of Grenoble IRIG-LPCVGrenoble Alpes UniversityCNRSCEAINRAE38000 GrenobleFrance molecular Physiology Department of Plant SciencesUniversity of CambridgeCambridge CB23EAUK Institute for Plant Biochemistry Cluster of Excellence on Plant Science(CEPLAS)Heinrich Heine UniversityUniversitätsstrasse 140225 DüsseldorfGermany Institute for Breeding Research on Agricultural Crops Federal Research Center for Cultivated Plants18190 SanitzGermany

Photosynthesis in crops and natural vegetation allows light energy to be converted into chemical energy and thus forms the foundation for almost all terrestrial trophic networks on *** efficiency of photosynthetic energy conversion plays a crucial role in determining the portion of incident solar radiation that can be used to generate plant biomass throughout a growth ***,alongside the factors such as resource availability,crop management,crop selection,maintenance costs,and intrinsic yield potential,photosynthetic energy use efficiency significantly influences crop *** efficiency is relevant to sustainability and food security because it affects water use efficiency,nutrient use efficiency,and land use *** review focuses specifically on the potential for improvements in photosynthetic efficiency to drive a sustainable increase in crop *** discuss bypassing photorespiration,enhancing light use efficiency,harnessing natural variation in photosynthetic parameters for breeding purposes,and adopting new-to-nature approaches that show promise for achieving unprecedented gains in photosynthetic efficiency.

关键词： photosynthesis photorespiration photorespiratory bypass natural variation synthetic biology plant metabolic engineering